Question

Regarding molarity, which of the following statements are correct?

a) Units of molarity gm-moles kg ${}^{-1}$

b) Molarity of dibasic acid is half of its normality

c)$\frac{Normality\times GEW}{GMW}$

d) Morality always equals to its molality

• A. a,b
• B. a,d
• C. b,c
• D. a,c

Answer 1

Answer: (C)

b,c

• Molarity $=$ $\frac{Massofsolute\times 1000}{MolarmassofsoluteV\left(inmL\right)}$

$\therefore$ Unit of molarity is $mol{L}^{-1}$ or $mol$ $d{m}^{-3}$

• Normality $=$ n $\times$ Molarity, for dibasic acid $n=2$

$\therefore$ Molarity $=$ $\frac{Normality}{2}$

Molarity $=$ $\frac{Normality\times GEW}{GMW}=\frac{Massperd{m}^3}{GMW}$

Hence, statements (b) and (c) are correct.